 |
| Titel |
Modelling effects of acid deposition and climate change on soil and run-off chemistry at Risdalsheia, Norway |
| VerfasserIn |
J. P. Mol-Dijkstra, H. Kros |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1027-5606
|
| Digitales Dokument |
URL |
| Erschienen |
In: Hydrology and Earth System Sciences ; 5, no. 3 ; Nr. 5, no. 3, S.487-498 |
| Datensatznummer |
250002569
|
| Publikation (Nr.) |
 copernicus.org/hess-5-487-2001.pdf |
|
|
|
|
|
| Zusammenfassung |
| Elevated carbon dioxide levels, caused by
anthropogenic emissions of carbon dioxide to the atmosphere, and higher
temperature may lead to increased plant growth and uptake
of nitrogen, but increased temperature may lead to increased nitrogen
mineralisation causing enhanced nitrogen leaching. The
overall result of both counteracting effects is largely unknown. To gain insight
into the long-term effects, the geochemical model SMART2
was applied using data from the catchment-scale experiments of the RAIN and
CLIMEX projects, conducted on boreal forest ecosystems at
Risdalsheia, southern Norway. These unique experiments at the ecosystem scale
provide information on the short-term effects and
interactions of nitrogen deposition and increased temperature and carbon dioxide
on carbon and nitrogen cycling and especially the run-off
chemistry. To predict changes in soil processes in response to climate change,
the model was extended by including the temperature effect
on mineralisation, nitrification, denitrification, aluminium dissolution and
mineral weathering. The extended model was tested on the two
manipulated catchments at Risdalsheia and long-term effects were evaluated by
performing long-time runs. The effects of climate change treatment,
which resulted in increased nitrogen fluxes at both catchments, were slightly
overestimated by SMART2. The temperature dependency of
mineralisation was simulated adequately but the temperature effect on
nitrification was slightly overestimated. Monitored changes in base cation
concentrations and pH were quite well simulated with SMART2. The long-term
simulations indicate that the increase in nitrogen run-off is
only a temporary effect; in the long-term, no effect on total nitrogen leaching
is predicted. At higher deposition levels the temporary increase
in nitrogen leaching lasts longer than at low deposition. Contrary to nitrogen
leaching, temperature increase leads to a permanent decrease
in aluminium concentrations and pH.
Keywords: elevated carbon
dioxide, temperature, forest ecosystem, modelling, nitrogen run-off. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|